The existence is reported of large reversible changes in the excess current of germanium, silicon, and gallium arsenide tunnel diodes subjected to highly localized stress. The relationship of this effect to the anisotropic stress effect recently reported by Rindner and Braun in conventionalp‐njunctions is discussed. It is suggested that both effects may arise from deep‐lying electronic states associated with strain‐induced lattice defects in the junction region. A consistent interpretation is presented of the tunnel diode excess current in terms of strain‐induced intermediate tunneling states, and of the conventional diode current in terms of strain‐induced generation‐recombination centers.